<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        div{
            width: 100px;
            height: 100px;
            background: red;
        }

        div:hover{
            /*background: #2fff3d;*/
            font-size: 30px;
        }

    </style>
</head>
<body>

        <div>
            div
        </div>

</body>
</html>
